The term "sixth sense" refers to a power of perception beyond the five senses, such as intuition or clairvoyance. It is often used to describe a natural ability to know about things before other people or to know things that others do not know. However, there is also a lesser-known "sixth sense" called proprioception, which allows us to keep track of where our body parts are in space. It is important to note that the concept of a "sixth sense" is not scientifically proven and is often associated with pseudoscience and paranormal beliefs.